AAP: Go-ahead at Ranger puzzles

Environmental groups want to know how the Ranger uranium mine in Kakadu National Park could be permitted to resume operations when the government report into the major industrial failure that led to the suspension of operations has not yet been made public.

Uranium processing has been halted since December after a leach tank collapsed, spilling about one million cubic litres of radioactive and acidic slurry at the site.

On Thursday, both the federal and Northern Territory governments approved the resumption of ore processing at the site by operators Energy Resources of Australia (ERA).

A progressive restart of processing will begin the same day.

"We acknowledge that this was a serious incident that damaged community confidence in our operations," ERA CEO Andrea Sutton said in a statement.

"The measures we have undertaken are designed to prevent anything similar happening in the future and to reassure our stakeholders and the broader community of the integrity of our operation."

But Nuclear-free NT campaigner Lauren Mellor said the approval was premature.

"It's extraordinary that ERA are getting a green light when the long-promised report that led to the suspension hasn't even seen daylight," the Australian Conservation Foundation's spokesman Dave Sweeney told AAP.

"If the government is confident in their process, then put the whole thing in the public domain and stop this approach of piecemeal assessment that happens behind closed doors."

The Gundjeihmi Aboriginal Corporation, which acts on behalf of the Mirarr traditional owners, said it accepts the restart for the time being.

"We're comfortable with this start-up, but in order for us to not all be back here in several years' time, we need a major culture shift at the mine," CEO Justin O'Brien said.

He said he was confident both levels of government would review the regulation of the mine to simplify it and bring it into line with broader industry practice on process safety codes.

"This is as much a failure on the part of the regulatory system as it is on the part of the mining company," Mr O'Brien said.

But Ranger is the most regulated site in the world, said NT Minister for Mines and Energy, Willem Westra van Holthe.

"It's constantly under scrutiny, and rightly so. The investigation makes sure Ranger operates more safely now than it did six months ago," he said.

He said there has been "absolutely no impact on Kakadu" as a result of the spill.

ERA expects the processing plant to return to normal production levels during the third quarter of this year, with the company's 2014 production of uranium oxide expected to be between 1,100 tonnes and 1,500 tonnes.